20 search usability guidelines

Search is one of the dominant ways that many customers interact with web sites. A good search engine needs to acknowledge the 'human' side of searching, which means dealing with spelling errors and synonyms (such as 'laptop' for 'notebook'). Google has set the standard for how search should look and behave, and many of these guidelines are based on this best practice.

List of search usability guidelines

The default search is intuitive to configure (no Boolean operators).

The search results page shows the user what was searched for and it is easy to edit and resubmit the search.

Search results are clear, useful and ranked by relevance.

The search results page makes it clear how many results were retrieved, and the number of results per page can be configured by the user.

If no results are returned, the system offers ideas or options for improving the query based on identifiable problems with the user's input.

The search engine handles empty queries gracefully.

The most common queries (as reflected in the site log) produce useful results.

The search engine includes templates, examples or hints on how to use it effectively.

The site includes a more powerful search interface available to help users refine their searches (preferably named "revise search" or "refine search", not "advanced search").

The search results page does not show duplicate results (either perceived duplicates or actual duplicates).

The search box is long enough to handle common query lengths.

Searches cover the entire web site, not a portion of it.

If the site allows users to set up a complex search, these searches can be saved and executed on a regular basis (so users can keep up-to-date with dynamic content).

The search interface is located where users will expect to find it (top right of page).

The search box and its controls are clearly labeled (multiple search boxes can be confusing).

The site supports people who want to browse and people who want to search.

The scope of the search is made explicit on the search results page and users can restrict the scope (if relevant to the task).

The search results page displays useful meta-information, such as the size of the document, the date that the document was created and the file type (Word, pdf etc.).

The search engine provides automatic spell checking and looks for plurals and synonyms.

The search engine provides an option for similarity search ("more like this").

How to use these guidelines

Work through each of the items in the list and mark your site as either conforming or not conforming to the guideline.

Remember that all guidelines are context specific. If you feel that a guideline does not apply to your site, it's OK to ignore it.

These guidelines are purposefully expressed as positive statements, so that when you feed the results back to the design team you can identify some strengths of the design before you launch into the problems.

About the author

Dr. David Travis (@userfocus on Twitter) holds a BSc and a PhD in Psychology and he is a Chartered Psychologist. He has worked in the fields of human factors, usability and user experience since 1989 and has published two books on usability. David helps both large firms and start ups connect with their customers and bring business ideas to market. If you like his articles, you'll love his online user experience training course.